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Components of Food

If you are trying to make heart-healthy changes to your lifestyle and diet, it's helpful to know some basics about nutrition, starting with the components of food.

Facts about calories

You need enough calories to give you energy, but no more than you can burn off. This is called an energy balance.

If you take in more calories than you burn, you gain weight.

If you take in fewer calories than you burn, you lose weight.

If you balance the two, you maintain your weight.

Even when you are dieting, you shouldn't cut back calories so much that you don't meet your energy needs. The number of calories you need depends on your age, gender, and activity level.

Facts about dietary cholesterol

Remember that "cholesterol-free" does not mean "fat-free."

Dietary cholesterol is a fat-like substance found in all foods from animals. This includes egg yolks, meat, poultry, fish, milk, and milk products.

Because your body makes cholesterol, you don't need it in your diet. But most people eat foods that contain cholesterol, so it's important not to eat too much cholesterol. The amount of cholesterol you eat can affect your blood cholesterol levels.

Types of fats

Fatty acids are the basic chemicals in fat. They may be saturated, polyunsaturated, monounsaturated, or trans fats. These fatty acids differ in their chemical makeup and structure, and in the way in which they affect your blood cholesterol levels.

Polyunsaturated fats

Monounsaturated fats

Don't seem to raise bad cholesterol levels. They may help boost HDL ("good") cholesterol in the blood. Higher HDL levels have been linked to a lower risk for heart disease.

Examples of monounsaturated fats include olive and canola oils.

Trans fats

These are byproducts of hydrogenation. This is a chemical process used to change liquid unsaturated fat to a more solid fat. Trans fats will be found in an ingredients list as a partially hydrogenated oil. Trans fatty acids are similar in structure to saturated fat. They may have a great impact on raising total cholesterol and LDL cholesterol levels. You should avoid trans fats as much as possible.

Examples of trans fats include stick margarine and fats found in commercially prepared cakes, cookies, and snack foods.

Your total fat intake should be no more than 30% of your daily calories.

Facts about fats

All fats contain about the same number of calories teaspoon for teaspoon. There is no such thing as low-fat fat.

Fat is the most concentrated source of calories. It supplies more than twice as many calories per gram as either carbohydrates or proteins (9 calories per gram compared with 4 calories per gram).

Most people get too much fat in their diet. This adds to health problems, like obesity, high blood cholesterol, and heart disease.

Coconut and palm oils have no cholesterol, but they are high in saturated fat. You should avoid these fats.

Facts about fiber

Your body doesn't digest most of the fiber you eat. Fiber can be soluble or insoluble.

Soluble fiber

Soluble fiber is found in foods like oat bran and dried beans. It can lower blood cholesterol in some people.

Insoluble fiber

Insoluble fiber is found in foods like wheat bran. It helps with weight control because it makes you feel full. It does not help lower cholesterol.

Facts about sodium

Salt is the main source of sodium in most people's diets.

Sodium and salt are not the same. A teaspoon of table salt contains 2,300 milligrams of sodium.

Sodium is a mineral needed to keep body fluids at a healthy level. It is also important for nerve function. It is found naturally in some foods, but most of the sodium in the average diet comes from seasonings and ingredients added to foods.

You need some sodium for good health, but most people get more than they need. In some people, too much sodium in the diet can raise blood pressure. This raises the risk for heart disease and stroke.